外文翻译题目离心泵学生姓名冯涛专业名称机械设计制造及其自动化指导教师史革盟2012年5月18日教学单位宝鸡文理学院学生学号200894014098编号JD2012JZ4098CentrifugalpumpTheconceptofcentrifugalCentrifugalinertiaistheperformanceofanobject,suchasumbrellasonthewaterdroplets,whentheumbrellaslowlyrotating,thewaterdropletswillfollowtheumbrellarotation,becausetheumbrellaandthefrictionofwaterdropletstodropasthecentripetalforceofshiran.However,iftheumbrellarotationspeed,thefrictionenoughtomakewaterdropletsinacircularmotion,thendropthesportfromtheumbrellatotheouteredge,likearopepullingthestonestodowithcircularmotion,ifthespeedistoofast,theropewilldisconnect,stoneswillbeflyingout.Thisistheso-calledcentrifugal.Centrifugalpumpisdesignedaccordingtothistheory,high-speedrotationoftheimpellerbladesrotatedrivenwater,throwwater,soastoachievethepurposeoftransportation.Goodvarietyofcentrifugalpumps,fromtheusecanbedividedintocivilandindustrialpumps;fromthetransmissionmediumcanbedividedintoclearwaterpump,trashpump,corrosionpumpandsoon.BasicstructurecentrifugalpumpBasicstructureofthecentrifugalpumpiscomposedofsixparts,namely:impeller,shaft,bearings,sealrings,stuffingbox.1centrifugalimpellerisacorecomponentofitsspeedandhighoutputforce,theimpellerbladehasplayedamajorroleintheassemblybeforetheimpellerbystatictest.Impellerontheinsideandoutsidesurfacesrequiredtobesmoothtoreduceflowfrictionloss.2,pump,alsoknownasthepumpcasing,whichisthemainwaterpump.Playaroleinsupportingfixed,andwiththeinstallationofthebearingbracketconnected.3,pumpshaftandmotorfunctionisconnectedbycoupling,themotortorquetransmissionimpeller,itisthetransferofmechanicalenergyofthemaincomponents.4,thebearingissetonthesupportshaftintheshaftcomponent,therearetwokindsofrollingbearingsandplainbearings.Rollingtousebutteraslubricantoiltobeappropriateis2/33/4sizetoomuchmayhaveafever,therearetoofewsoundandheat!Pumpbearingstructureistransparenttotheoilusedforlubricants,fueltotheoillevelline.Toomuchoiltobeleakingalongtheshaftanddrift*,toolittleoverheatedbearingsandalsoburntheaccident!Bearinginthepumpduringoperationthemaximumtemperatureof85℃inthegeneralrunof60degrees,ifweshouldfindoutthereasonshigh(whetherimpurities,oilisblack,iswater)andtimelymanner5,sealingring,alsoknownasleakagereductionring.Impellerandpumpcasingofimportsoverthegapbetweenhigh-pressureareascausethepump'swaterflowthroughthegapareaoflowpressureaffectingthepumpoutwater,reducingefficiency!Gapistoosmallwillcausetheimpellerandpumpcasingfrictionandwear.Inordertoincreasethereturntoreducetheinternalleakageresistanceanddelayoftheimpellerandpumpcasinglifeofthepumpimpellershelledgeandforeignaidjunctionwithsealingring,sealingthegapremainedat0.25~1.10mmhydrometer.6,stuffingmainlybythepacking,sealring,fillertube,packinggland,sealtubes.Themainfunctionofstuffingistobeclosedbetweenthepumpcasingandshaftgap,nottopumpthewaterdoesnotflowouttonotletoutsideairintothepump.Alwaysmaintainthevacuuminsidethepump!Whenthepumpandfillthewatersealfrictiondependsontheheatpipetoliveonthewatertosealcircletofillthecooling!Tomaintainthenormaloperationofpumps.Socheckthepumptorunduringthetourofinspectionofthestuffingisthespecialattention!Aboutrunning600hoursonthepackingshouldbereplaced.TheworkingprincipleofcentrifugalpumpImpellerinstalledinsidethepumpcasing2andfastenedintheshaft3,theshaftdirectlydrivenbythemotor.Centralhasaliquidpumpcasingandsuctionpipeinhaling45connection.Liquidthroughthebottomvalve6andthesuctiontubeintothepump.Pumpcasingliquiddischargeoutletonthedischargepipe8and9connections.Beforestartingthepump,thepumpistransportedshellfilledwithliquid;starts,starts,theimpellershaftdrivenbythehigh-speedrotation,theliquidbetweenthebladesmustrotatewith.Undertheactionofcentrifugalforce,theliquidwasthrownfromthecenteroftheouteredgeoftheimpellerandgetenergyfromtheimpellerathighspeedintothevolutepumpoutershell.Inthespiralcase,thefluidflow,graduallyastheexpansionsloweddowninturnpartofthekineticenergyintostaticpressureenergy,thefinaldischargeathigherpressureintothepipeline,senttotheneedtoplace.Theflowofliquidfromthecenteroftheouteredgeoftheimpellerwhentheimpellercenterintheformationofacertainvacuum,duetothepressuretankabovetheliquidlevelisgreaterthanthepressureattheentrancetothepump,theliquidwillbepressedintotheimpellerinarow.Canbeseen,aslongastheconstantlyrotatingimpeller,theliquidwillcontinuetobesuckedanddischarged.ThephenomenonofgastieWhenthepumpcasingtotheexistenceofair,becauseairdensityismuchsmallerthanthedensityoftheliquidcausedbyasmallercentrifugalforce.Thus,thetankliquidlevelabovetheentranceandthepressuredifferencebetweenpumpsufficientfluidpressurewithinthetankintothepump,thatisnotself-primingcentrifugalpump,sopumpcannottransportliquid,suchphenomenonisknownasgastiephenomenon.Inordertopumpfullofliquid,usuallyinstalledinthesuctionpipealongthebottomofthebottomfiltervalve,thebottomvalveuntilthevalve,thefilteristopreventsolidmaterialintothepumpimpellerdamageorimpedethenormaloperationofthepump.ThemaincomponentsofcentrifugalpumpMaincomponentsareimpeller,pumpcasingandshaftsealdevices.1impellerTheroleoftheimpelleristheorigina